1. Field of the Invention
The present invention relates to a high-pressure hydrogen producing apparatus.
2. Discussion of the Background
Generally, hydrogen is used as a fuel gas to be used in the power generation reaction of a fuel cell. This hydrogen gas is generated by a water electrolysis apparatus. The water electrolysis apparatus employs a solid polymer electrolyte membrane (ion exchange membrane) for decomposing water to generate hydrogen (and oxygen). Electrode catalyst layers are disposed on the respective sides of the solid polymer electrolyte membrane, forming an electrolyte membrane/electrode assembly. Current collectors are disposed on the respective sides of the electrolyte membrane/electrode assembly, making up a unit cell.
A plurality of such units are stacked to form a cell unit. A voltage is applied across the cell unit while water is supplied to the current collectors on the anode side. On the anodes of the electrolyte membrane/electrode assembly, water is decomposed to produce hydrogen ions (protons). The hydrogen ions move through the solid polymer electrolyte membranes to the cathodes to be combined with electrons to generate hydrogen. On the anodes, oxygen generated together with hydrogen is discharged with excess water from the cell unit.